{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import numpy as np\n",
    "\n",
    "import pandas as pd\n",
    "\n",
    "from pandas import Series,DataFrame"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# csv类型文件呢，文本文件，excel打开，格式化的文件，所以excel可以直接读取成表格\n",
    "# 美国人口的一些情况\n",
    "# pandas分析一下美国人口数据"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
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       "    }\n",
       "\n",
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       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>California</td>\n",
       "      <td>163707</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>Colorado</td>\n",
       "      <td>104100</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>Connecticut</td>\n",
       "      <td>5544</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>Delaware</td>\n",
       "      <td>1954</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>Florida</td>\n",
       "      <td>65758</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>Georgia</td>\n",
       "      <td>59441</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>Hawaii</td>\n",
       "      <td>10932</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>Idaho</td>\n",
       "      <td>83574</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>Illinois</td>\n",
       "      <td>57918</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>Indiana</td>\n",
       "      <td>36420</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>Iowa</td>\n",
       "      <td>56276</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>Kansas</td>\n",
       "      <td>82282</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>Kentucky</td>\n",
       "      <td>40411</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>Louisiana</td>\n",
       "      <td>51843</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>Maine</td>\n",
       "      <td>35387</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>Maryland</td>\n",
       "      <td>12407</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>10555</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>Michigan</td>\n",
       "      <td>96810</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>Minnesota</td>\n",
       "      <td>86943</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>Mississippi</td>\n",
       "      <td>48434</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>Missouri</td>\n",
       "      <td>69709</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>Montana</td>\n",
       "      <td>147046</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>Nebraska</td>\n",
       "      <td>77358</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>Nevada</td>\n",
       "      <td>110567</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>9351</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>New Jersey</td>\n",
       "      <td>8722</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>30</th>\n",
       "      <td>New Mexico</td>\n",
       "      <td>121593</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>31</th>\n",
       "      <td>New York</td>\n",
       "      <td>54475</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>32</th>\n",
       "      <td>North Carolina</td>\n",
       "      <td>53821</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>33</th>\n",
       "      <td>North Dakota</td>\n",
       "      <td>70704</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>34</th>\n",
       "      <td>Ohio</td>\n",
       "      <td>44828</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>35</th>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>69903</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>36</th>\n",
       "      <td>Oregon</td>\n",
       "      <td>98386</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>37</th>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>46058</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>38</th>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>1545</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>39</th>\n",
       "      <td>South Carolina</td>\n",
       "      <td>32007</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>40</th>\n",
       "      <td>South Dakota</td>\n",
       "      <td>77121</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>41</th>\n",
       "      <td>Tennessee</td>\n",
       "      <td>42146</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>42</th>\n",
       "      <td>Texas</td>\n",
       "      <td>268601</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>43</th>\n",
       "      <td>Utah</td>\n",
       "      <td>84904</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>44</th>\n",
       "      <td>Vermont</td>\n",
       "      <td>9615</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>45</th>\n",
       "      <td>Virginia</td>\n",
       "      <td>42769</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>46</th>\n",
       "      <td>Washington</td>\n",
       "      <td>71303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>47</th>\n",
       "      <td>West Virginia</td>\n",
       "      <td>24231</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>48</th>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>65503</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>49</th>\n",
       "      <td>Wyoming</td>\n",
       "      <td>97818</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50</th>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>68</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>51</th>\n",
       "      <td>Puerto Rico</td>\n",
       "      <td>3515</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                   state  area (sq. mi)\n",
       "0                Alabama          52423\n",
       "1                 Alaska         656425\n",
       "2                Arizona         114006\n",
       "3               Arkansas          53182\n",
       "4             California         163707\n",
       "5               Colorado         104100\n",
       "6            Connecticut           5544\n",
       "7               Delaware           1954\n",
       "8                Florida          65758\n",
       "9                Georgia          59441\n",
       "10                Hawaii          10932\n",
       "11                 Idaho          83574\n",
       "12              Illinois          57918\n",
       "13               Indiana          36420\n",
       "14                  Iowa          56276\n",
       "15                Kansas          82282\n",
       "16              Kentucky          40411\n",
       "17             Louisiana          51843\n",
       "18                 Maine          35387\n",
       "19              Maryland          12407\n",
       "20         Massachusetts          10555\n",
       "21              Michigan          96810\n",
       "22             Minnesota          86943\n",
       "23           Mississippi          48434\n",
       "24              Missouri          69709\n",
       "25               Montana         147046\n",
       "26              Nebraska          77358\n",
       "27                Nevada         110567\n",
       "28         New Hampshire           9351\n",
       "29            New Jersey           8722\n",
       "30            New Mexico         121593\n",
       "31              New York          54475\n",
       "32        North Carolina          53821\n",
       "33          North Dakota          70704\n",
       "34                  Ohio          44828\n",
       "35              Oklahoma          69903\n",
       "36                Oregon          98386\n",
       "37          Pennsylvania          46058\n",
       "38          Rhode Island           1545\n",
       "39        South Carolina          32007\n",
       "40          South Dakota          77121\n",
       "41             Tennessee          42146\n",
       "42                 Texas         268601\n",
       "43                  Utah          84904\n",
       "44               Vermont           9615\n",
       "45              Virginia          42769\n",
       "46            Washington          71303\n",
       "47         West Virginia          24231\n",
       "48             Wisconsin          65503\n",
       "49               Wyoming          97818\n",
       "50  District of Columbia             68\n",
       "51           Puerto Rico           3515"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 美国各州的面积\n",
    "areas = pd.read_csv('./state-areas.csv')\n",
    "areas"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(52, 2)"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "areas.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state</th>\n",
       "      <th>abbreviation</th>\n",
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       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
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       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Alaska</td>\n",
       "      <td>AK</td>\n",
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       "      <th>2</th>\n",
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       "      <th>4</th>\n",
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       "      <td>CA</td>\n",
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       "      <th>5</th>\n",
       "      <td>Colorado</td>\n",
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       "      <th>6</th>\n",
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       "      <th>7</th>\n",
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       "      <td>DE</td>\n",
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       "      <th>8</th>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>DC</td>\n",
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       "      <th>9</th>\n",
       "      <td>Florida</td>\n",
       "      <td>FL</td>\n",
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       "      <th>10</th>\n",
       "      <td>Georgia</td>\n",
       "      <td>GA</td>\n",
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       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>Hawaii</td>\n",
       "      <td>HI</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>Idaho</td>\n",
       "      <td>ID</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>Illinois</td>\n",
       "      <td>IL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>Indiana</td>\n",
       "      <td>IN</td>\n",
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       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>Iowa</td>\n",
       "      <td>IA</td>\n",
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       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>Kansas</td>\n",
       "      <td>KS</td>\n",
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       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>Kentucky</td>\n",
       "      <td>KY</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>Louisiana</td>\n",
       "      <td>LA</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>Maine</td>\n",
       "      <td>ME</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>Montana</td>\n",
       "      <td>MT</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>Nebraska</td>\n",
       "      <td>NE</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>Nevada</td>\n",
       "      <td>NV</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>NH</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>New Jersey</td>\n",
       "      <td>NJ</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>New Mexico</td>\n",
       "      <td>NM</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>New York</td>\n",
       "      <td>NY</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>North Carolina</td>\n",
       "      <td>NC</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>North Dakota</td>\n",
       "      <td>ND</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>Ohio</td>\n",
       "      <td>OH</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>30</th>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>OK</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>31</th>\n",
       "      <td>Oregon</td>\n",
       "      <td>OR</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>32</th>\n",
       "      <td>Maryland</td>\n",
       "      <td>MD</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>33</th>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>MA</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>34</th>\n",
       "      <td>Michigan</td>\n",
       "      <td>MI</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>35</th>\n",
       "      <td>Minnesota</td>\n",
       "      <td>MN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>36</th>\n",
       "      <td>Mississippi</td>\n",
       "      <td>MS</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>37</th>\n",
       "      <td>Missouri</td>\n",
       "      <td>MO</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>38</th>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>PA</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>39</th>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>RI</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>40</th>\n",
       "      <td>South Carolina</td>\n",
       "      <td>SC</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>41</th>\n",
       "      <td>South Dakota</td>\n",
       "      <td>SD</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>42</th>\n",
       "      <td>Tennessee</td>\n",
       "      <td>TN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>43</th>\n",
       "      <td>Texas</td>\n",
       "      <td>TX</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>44</th>\n",
       "      <td>Utah</td>\n",
       "      <td>UT</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>45</th>\n",
       "      <td>Vermont</td>\n",
       "      <td>VT</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>46</th>\n",
       "      <td>Virginia</td>\n",
       "      <td>VA</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>47</th>\n",
       "      <td>Washington</td>\n",
       "      <td>WA</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>48</th>\n",
       "      <td>West Virginia</td>\n",
       "      <td>WV</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>49</th>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>WI</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50</th>\n",
       "      <td>Wyoming</td>\n",
       "      <td>WY</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                   state abbreviation\n",
       "0                Alabama           AL\n",
       "1                 Alaska           AK\n",
       "2                Arizona           AZ\n",
       "3               Arkansas           AR\n",
       "4             California           CA\n",
       "5               Colorado           CO\n",
       "6            Connecticut           CT\n",
       "7               Delaware           DE\n",
       "8   District of Columbia           DC\n",
       "9                Florida           FL\n",
       "10               Georgia           GA\n",
       "11                Hawaii           HI\n",
       "12                 Idaho           ID\n",
       "13              Illinois           IL\n",
       "14               Indiana           IN\n",
       "15                  Iowa           IA\n",
       "16                Kansas           KS\n",
       "17              Kentucky           KY\n",
       "18             Louisiana           LA\n",
       "19                 Maine           ME\n",
       "20               Montana           MT\n",
       "21              Nebraska           NE\n",
       "22                Nevada           NV\n",
       "23         New Hampshire           NH\n",
       "24            New Jersey           NJ\n",
       "25            New Mexico           NM\n",
       "26              New York           NY\n",
       "27        North Carolina           NC\n",
       "28          North Dakota           ND\n",
       "29                  Ohio           OH\n",
       "30              Oklahoma           OK\n",
       "31                Oregon           OR\n",
       "32              Maryland           MD\n",
       "33         Massachusetts           MA\n",
       "34              Michigan           MI\n",
       "35             Minnesota           MN\n",
       "36           Mississippi           MS\n",
       "37              Missouri           MO\n",
       "38          Pennsylvania           PA\n",
       "39          Rhode Island           RI\n",
       "40        South Carolina           SC\n",
       "41          South Dakota           SD\n",
       "42             Tennessee           TN\n",
       "43                 Texas           TX\n",
       "44                  Utah           UT\n",
       "45               Vermont           VT\n",
       "46              Virginia           VA\n",
       "47            Washington           WA\n",
       "48         West Virginia           WV\n",
       "49             Wisconsin           WI\n",
       "50               Wyoming           WY"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 美国各州 缩写\n",
    "abbrevs = pd.read_csv('./state-abbrevs.csv')\n",
    "abbrevs"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(51, 2)"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "abbrevs.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2011</td>\n",
       "      <td>4801627.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2009</td>\n",
       "      <td>4757938.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2009</td>\n",
       "      <td>1134192.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2013</td>\n",
       "      <td>1111481.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2013</td>\n",
       "      <td>4833722.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2007</td>\n",
       "      <td>4672840.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2007</td>\n",
       "      <td>1132296.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2008</td>\n",
       "      <td>4718206.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2008</td>\n",
       "      <td>1134927.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2005</td>\n",
       "      <td>4569805.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2005</td>\n",
       "      <td>1117229.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2006</td>\n",
       "      <td>4628981.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2006</td>\n",
       "      <td>1126798.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2004</td>\n",
       "      <td>4530729.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2004</td>\n",
       "      <td>1113662.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2003</td>\n",
       "      <td>4503491.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2003</td>\n",
       "      <td>1113083.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2001</td>\n",
       "      <td>4467634.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2001</td>\n",
       "      <td>1120409.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2002</td>\n",
       "      <td>4480089.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2002</td>\n",
       "      <td>1116590.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>1999</td>\n",
       "      <td>1121287.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>1999</td>\n",
       "      <td>4430141.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2000</td>\n",
       "      <td>4452173.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2000</td>\n",
       "      <td>1122273.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2514</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>1999</td>\n",
       "      <td>71946051.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2515</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2000</td>\n",
       "      <td>282162411.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2516</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2000</td>\n",
       "      <td>72376189.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2517</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>1999</td>\n",
       "      <td>279040181.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2518</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2001</td>\n",
       "      <td>284968955.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2519</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2001</td>\n",
       "      <td>72671175.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2520</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2002</td>\n",
       "      <td>287625193.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2521</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2002</td>\n",
       "      <td>72936457.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2522</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2003</td>\n",
       "      <td>290107933.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2523</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2003</td>\n",
       "      <td>73100758.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2524</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2004</td>\n",
       "      <td>292805298.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2525</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2004</td>\n",
       "      <td>73297735.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2526</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2005</td>\n",
       "      <td>295516599.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2527</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2005</td>\n",
       "      <td>73523669.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2528</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2006</td>\n",
       "      <td>298379912.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2529</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2006</td>\n",
       "      <td>73757714.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2530</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2007</td>\n",
       "      <td>301231207.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2531</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2007</td>\n",
       "      <td>74019405.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2532</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2008</td>\n",
       "      <td>304093966.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2533</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2008</td>\n",
       "      <td>74104602.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2534</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2013</td>\n",
       "      <td>73585872.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2535</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2013</td>\n",
       "      <td>316128839.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2536</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2009</td>\n",
       "      <td>306771529.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2537</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2009</td>\n",
       "      <td>74134167.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2538</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>74119556.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2539</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>309326295.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2540</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>73902222.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2541</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2011</td>\n",
       "      <td>311582564.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2542</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>73708179.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2543</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>313873685.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>2544 rows × 4 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "     state/region     ages  year   population\n",
       "0              AL  under18  2012    1117489.0\n",
       "1              AL    total  2012    4817528.0\n",
       "2              AL  under18  2010    1130966.0\n",
       "3              AL    total  2010    4785570.0\n",
       "4              AL  under18  2011    1125763.0\n",
       "5              AL    total  2011    4801627.0\n",
       "6              AL    total  2009    4757938.0\n",
       "7              AL  under18  2009    1134192.0\n",
       "8              AL  under18  2013    1111481.0\n",
       "9              AL    total  2013    4833722.0\n",
       "10             AL    total  2007    4672840.0\n",
       "11             AL  under18  2007    1132296.0\n",
       "12             AL    total  2008    4718206.0\n",
       "13             AL  under18  2008    1134927.0\n",
       "14             AL    total  2005    4569805.0\n",
       "15             AL  under18  2005    1117229.0\n",
       "16             AL    total  2006    4628981.0\n",
       "17             AL  under18  2006    1126798.0\n",
       "18             AL    total  2004    4530729.0\n",
       "19             AL  under18  2004    1113662.0\n",
       "20             AL    total  2003    4503491.0\n",
       "21             AL  under18  2003    1113083.0\n",
       "22             AL    total  2001    4467634.0\n",
       "23             AL  under18  2001    1120409.0\n",
       "24             AL    total  2002    4480089.0\n",
       "25             AL  under18  2002    1116590.0\n",
       "26             AL  under18  1999    1121287.0\n",
       "27             AL    total  1999    4430141.0\n",
       "28             AL    total  2000    4452173.0\n",
       "29             AL  under18  2000    1122273.0\n",
       "...           ...      ...   ...          ...\n",
       "2514          USA  under18  1999   71946051.0\n",
       "2515          USA    total  2000  282162411.0\n",
       "2516          USA  under18  2000   72376189.0\n",
       "2517          USA    total  1999  279040181.0\n",
       "2518          USA    total  2001  284968955.0\n",
       "2519          USA  under18  2001   72671175.0\n",
       "2520          USA    total  2002  287625193.0\n",
       "2521          USA  under18  2002   72936457.0\n",
       "2522          USA    total  2003  290107933.0\n",
       "2523          USA  under18  2003   73100758.0\n",
       "2524          USA    total  2004  292805298.0\n",
       "2525          USA  under18  2004   73297735.0\n",
       "2526          USA    total  2005  295516599.0\n",
       "2527          USA  under18  2005   73523669.0\n",
       "2528          USA    total  2006  298379912.0\n",
       "2529          USA  under18  2006   73757714.0\n",
       "2530          USA    total  2007  301231207.0\n",
       "2531          USA  under18  2007   74019405.0\n",
       "2532          USA    total  2008  304093966.0\n",
       "2533          USA  under18  2008   74104602.0\n",
       "2534          USA  under18  2013   73585872.0\n",
       "2535          USA    total  2013  316128839.0\n",
       "2536          USA    total  2009  306771529.0\n",
       "2537          USA  under18  2009   74134167.0\n",
       "2538          USA  under18  2010   74119556.0\n",
       "2539          USA    total  2010  309326295.0\n",
       "2540          USA  under18  2011   73902222.0\n",
       "2541          USA    total  2011  311582564.0\n",
       "2542          USA  under18  2012   73708179.0\n",
       "2543          USA    total  2012  313873685.0\n",
       "\n",
       "[2544 rows x 4 columns]"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 美国的人口数据\n",
    "pop = pd.read_csv('./state-population.csv')\n",
    "pop"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2544, 4)"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {
    "scrolled": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population\n",
       "0           AL  under18  2012   1117489.0\n",
       "1           AL    total  2012   4817528.0\n",
       "2           AL  under18  2010   1130966.0\n",
       "3           AL    total  2010   4785570.0\n",
       "4           AL  under18  2011   1125763.0"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state</th>\n",
       "      <th>abbreviation</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Alaska</td>\n",
       "      <td>AK</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Arizona</td>\n",
       "      <td>AZ</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Arkansas</td>\n",
       "      <td>AR</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>California</td>\n",
       "      <td>CA</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "        state abbreviation\n",
       "0     Alabama           AL\n",
       "1      Alaska           AK\n",
       "2     Arizona           AZ\n",
       "3    Arkansas           AR\n",
       "4  California           CA"
      ]
     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "abbrevs.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2544, 4)"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    },
    {
     "data": {
      "text/plain": [
       "(51, 2)"
      ]
     },
     "metadata": {},
     "output_type": "display_data"
    }
   ],
   "source": [
    "display(pop.shape,abbrevs.shape)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2544, 6)"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 级联时，数据变少了96个，哪些数据变少\n",
    "# inner内连接，outer叫做外连接\n",
    "pop2 = pop.merge(abbrevs,how = 'outer',left_on='state/region',right_on='abbreviation')\n",
    "pop2.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region    False\n",
       "ages            False\n",
       "year            False\n",
       "population       True\n",
       "state            True\n",
       "abbreviation     True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 17,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 前三列没有空值\n",
    "pop2.isnull().any()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>abbreviation</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>AL</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population    state abbreviation\n",
       "0           AL  under18  2012   1117489.0  Alabama           AL\n",
       "1           AL    total  2012   4817528.0  Alabama           AL\n",
       "2           AL  under18  2010   1130966.0  Alabama           AL\n",
       "3           AL    total  2010   4785570.0  Alabama           AL\n",
       "4           AL  under18  2011   1125763.0  Alabama           AL"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [],
   "source": [
    "# 删除一列\n",
    "pop2.drop(labels = 'abbreviation',axis = 1,inplace=True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population    state\n",
       "0           AL  under18  2012   1117489.0  Alabama\n",
       "1           AL    total  2012   4817528.0  Alabama\n",
       "2           AL  under18  2010   1130966.0  Alabama\n",
       "3           AL    total  2010   4785570.0  Alabama\n",
       "4           AL  under18  2011   1125763.0  Alabama"
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region    False\n",
       "ages            False\n",
       "year            False\n",
       "population       True\n",
       "state            True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 22,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.isnull().any()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0       False\n",
       "1       False\n",
       "2       False\n",
       "3       False\n",
       "4       False\n",
       "5       False\n",
       "6       False\n",
       "7       False\n",
       "8       False\n",
       "9       False\n",
       "10      False\n",
       "11      False\n",
       "12      False\n",
       "13      False\n",
       "14      False\n",
       "15      False\n",
       "16      False\n",
       "17      False\n",
       "18      False\n",
       "19      False\n",
       "20      False\n",
       "21      False\n",
       "22      False\n",
       "23      False\n",
       "24      False\n",
       "25      False\n",
       "26      False\n",
       "27      False\n",
       "28      False\n",
       "29      False\n",
       "        ...  \n",
       "2514     True\n",
       "2515     True\n",
       "2516     True\n",
       "2517     True\n",
       "2518     True\n",
       "2519     True\n",
       "2520     True\n",
       "2521     True\n",
       "2522     True\n",
       "2523     True\n",
       "2524     True\n",
       "2525     True\n",
       "2526     True\n",
       "2527     True\n",
       "2528     True\n",
       "2529     True\n",
       "2530     True\n",
       "2531     True\n",
       "2532     True\n",
       "2533     True\n",
       "2534     True\n",
       "2535     True\n",
       "2536     True\n",
       "2537     True\n",
       "2538     True\n",
       "2539     True\n",
       "2540     True\n",
       "2541     True\n",
       "2542     True\n",
       "2543     True\n",
       "Name: state, Length: 2544, dtype: bool"
      ]
     },
     "execution_count": 24,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 定位为空的数据\n",
    "cond = pop2['state'].isnull()\n",
    "cond"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['PR', 'USA'], dtype=object)"
      ]
     },
     "execution_count": 27,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 只有当state为空，返回，为空时True\n",
    "# 去重操作，非重复值\n",
    "pop2[cond]['state/region'].unique()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(51, 2)"
      ]
     },
     "execution_count": 30,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "abbrevs.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(52, 2)"
      ]
     },
     "execution_count": 31,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "areas.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423</td>\n",
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       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>California</td>\n",
       "      <td>163707</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>Colorado</td>\n",
       "      <td>104100</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>Connecticut</td>\n",
       "      <td>5544</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>Delaware</td>\n",
       "      <td>1954</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>Florida</td>\n",
       "      <td>65758</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>Georgia</td>\n",
       "      <td>59441</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>Hawaii</td>\n",
       "      <td>10932</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>Idaho</td>\n",
       "      <td>83574</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>Illinois</td>\n",
       "      <td>57918</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>Indiana</td>\n",
       "      <td>36420</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>Iowa</td>\n",
       "      <td>56276</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>Kansas</td>\n",
       "      <td>82282</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>Kentucky</td>\n",
       "      <td>40411</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>Louisiana</td>\n",
       "      <td>51843</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>Maine</td>\n",
       "      <td>35387</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>Maryland</td>\n",
       "      <td>12407</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>10555</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>Michigan</td>\n",
       "      <td>96810</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>Minnesota</td>\n",
       "      <td>86943</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>Mississippi</td>\n",
       "      <td>48434</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>Missouri</td>\n",
       "      <td>69709</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>Montana</td>\n",
       "      <td>147046</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>Nebraska</td>\n",
       "      <td>77358</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>Nevada</td>\n",
       "      <td>110567</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>9351</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>New Jersey</td>\n",
       "      <td>8722</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>30</th>\n",
       "      <td>New Mexico</td>\n",
       "      <td>121593</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>31</th>\n",
       "      <td>New York</td>\n",
       "      <td>54475</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>32</th>\n",
       "      <td>North Carolina</td>\n",
       "      <td>53821</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>33</th>\n",
       "      <td>North Dakota</td>\n",
       "      <td>70704</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>34</th>\n",
       "      <td>Ohio</td>\n",
       "      <td>44828</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>35</th>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>69903</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>36</th>\n",
       "      <td>Oregon</td>\n",
       "      <td>98386</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>37</th>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>46058</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>38</th>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>1545</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>39</th>\n",
       "      <td>South Carolina</td>\n",
       "      <td>32007</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>40</th>\n",
       "      <td>South Dakota</td>\n",
       "      <td>77121</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>41</th>\n",
       "      <td>Tennessee</td>\n",
       "      <td>42146</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>42</th>\n",
       "      <td>Texas</td>\n",
       "      <td>268601</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>43</th>\n",
       "      <td>Utah</td>\n",
       "      <td>84904</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>44</th>\n",
       "      <td>Vermont</td>\n",
       "      <td>9615</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>45</th>\n",
       "      <td>Virginia</td>\n",
       "      <td>42769</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>46</th>\n",
       "      <td>Washington</td>\n",
       "      <td>71303</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>47</th>\n",
       "      <td>West Virginia</td>\n",
       "      <td>24231</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>48</th>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>65503</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>49</th>\n",
       "      <td>Wyoming</td>\n",
       "      <td>97818</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50</th>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>68</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>51</th>\n",
       "      <td>Puerto Rico</td>\n",
       "      <td>3515</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                   state  area (sq. mi)\n",
       "0                Alabama          52423\n",
       "1                 Alaska         656425\n",
       "2                Arizona         114006\n",
       "3               Arkansas          53182\n",
       "4             California         163707\n",
       "5               Colorado         104100\n",
       "6            Connecticut           5544\n",
       "7               Delaware           1954\n",
       "8                Florida          65758\n",
       "9                Georgia          59441\n",
       "10                Hawaii          10932\n",
       "11                 Idaho          83574\n",
       "12              Illinois          57918\n",
       "13               Indiana          36420\n",
       "14                  Iowa          56276\n",
       "15                Kansas          82282\n",
       "16              Kentucky          40411\n",
       "17             Louisiana          51843\n",
       "18                 Maine          35387\n",
       "19              Maryland          12407\n",
       "20         Massachusetts          10555\n",
       "21              Michigan          96810\n",
       "22             Minnesota          86943\n",
       "23           Mississippi          48434\n",
       "24              Missouri          69709\n",
       "25               Montana         147046\n",
       "26              Nebraska          77358\n",
       "27                Nevada         110567\n",
       "28         New Hampshire           9351\n",
       "29            New Jersey           8722\n",
       "30            New Mexico         121593\n",
       "31              New York          54475\n",
       "32        North Carolina          53821\n",
       "33          North Dakota          70704\n",
       "34                  Ohio          44828\n",
       "35              Oklahoma          69903\n",
       "36                Oregon          98386\n",
       "37          Pennsylvania          46058\n",
       "38          Rhode Island           1545\n",
       "39        South Carolina          32007\n",
       "40          South Dakota          77121\n",
       "41             Tennessee          42146\n",
       "42                 Texas         268601\n",
       "43                  Utah          84904\n",
       "44               Vermont           9615\n",
       "45              Virginia          42769\n",
       "46            Washington          71303\n",
       "47         West Virginia          24231\n",
       "48             Wisconsin          65503\n",
       "49               Wyoming          97818\n",
       "50  District of Columbia             68\n",
       "51           Puerto Rico           3515"
      ]
     },
     "execution_count": 32,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "areas"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0       False\n",
       "1       False\n",
       "2       False\n",
       "3       False\n",
       "4       False\n",
       "5       False\n",
       "6       False\n",
       "7       False\n",
       "8       False\n",
       "9       False\n",
       "10      False\n",
       "11      False\n",
       "12      False\n",
       "13      False\n",
       "14      False\n",
       "15      False\n",
       "16      False\n",
       "17      False\n",
       "18      False\n",
       "19      False\n",
       "20      False\n",
       "21      False\n",
       "22      False\n",
       "23      False\n",
       "24      False\n",
       "25      False\n",
       "26      False\n",
       "27      False\n",
       "28      False\n",
       "29      False\n",
       "        ...  \n",
       "2514    False\n",
       "2515    False\n",
       "2516    False\n",
       "2517    False\n",
       "2518    False\n",
       "2519    False\n",
       "2520    False\n",
       "2521    False\n",
       "2522    False\n",
       "2523    False\n",
       "2524    False\n",
       "2525    False\n",
       "2526    False\n",
       "2527    False\n",
       "2528    False\n",
       "2529    False\n",
       "2530    False\n",
       "2531    False\n",
       "2532    False\n",
       "2533    False\n",
       "2534    False\n",
       "2535    False\n",
       "2536    False\n",
       "2537    False\n",
       "2538    False\n",
       "2539    False\n",
       "2540    False\n",
       "2541    False\n",
       "2542    False\n",
       "2543    False\n",
       "Name: state/region, Length: 2544, dtype: bool"
      ]
     },
     "execution_count": 34,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cond = pop2['state/region'] == 'PR'\n",
    "cond"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "d:\\python36\\lib\\site-packages\\ipykernel_launcher.py:1: SettingWithCopyWarning: \n",
      "A value is trying to be set on a copy of a slice from a DataFrame\n",
      "\n",
      "See the caveats in the documentation: http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy\n",
      "  \"\"\"Entry point for launching an IPython kernel.\n"
     ]
    }
   ],
   "source": [
    "pop2['state'][cond] = 'Puerto Rico'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "d:\\python36\\lib\\site-packages\\ipykernel_launcher.py:2: SettingWithCopyWarning: \n",
      "A value is trying to be set on a copy of a slice from a DataFrame\n",
      "\n",
      "See the caveats in the documentation: http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy\n",
      "  \n"
     ]
    }
   ],
   "source": [
    "cond = pop2['state/region'] == 'USA'\n",
    "pop2['state'][cond] = 'United State'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 39,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region    False\n",
       "ages            False\n",
       "year            False\n",
       "population       True\n",
       "state           False\n",
       "dtype: bool"
      ]
     },
     "execution_count": 39,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.isnull().any()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 42,
   "metadata": {
    "scrolled": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(20, 5)"
      ]
     },
     "execution_count": 42,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cond = pop2['population'].isnull()\n",
    "pop2[cond].shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 43,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2544, 5)"
      ]
     },
     "execution_count": 43,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 45,
   "metadata": {},
   "outputs": [],
   "source": [
    "# 将难于进行补全的空数据进行删除\n",
    "pop2.dropna(inplace=True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 46,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2524, 5)"
      ]
     },
     "execution_count": 46,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 47,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region    False\n",
       "ages            False\n",
       "year            False\n",
       "population      False\n",
       "state           False\n",
       "dtype: bool"
      ]
     },
     "execution_count": 47,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.isnull().any()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 48,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region    True\n",
       "ages            True\n",
       "year            True\n",
       "population      True\n",
       "state           True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 48,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.notnull().all()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 50,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>California</td>\n",
       "      <td>163707</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "        state  area (sq. mi)\n",
       "0     Alabama          52423\n",
       "1      Alaska         656425\n",
       "2     Arizona         114006\n",
       "3    Arkansas          53182\n",
       "4  California         163707"
      ]
     },
     "execution_count": 50,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "areas.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 49,
   "metadata": {
    "scrolled": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "      <td>Alabama</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population    state\n",
       "0           AL  under18  2012   1117489.0  Alabama\n",
       "1           AL    total  2012   4817528.0  Alabama\n",
       "2           AL  under18  2010   1130966.0  Alabama\n",
       "3           AL    total  2010   4785570.0  Alabama\n",
       "4           AL  under18  2011   1125763.0  Alabama"
      ]
     },
     "execution_count": 49,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop2.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 51,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(2524, 6)"
      ]
     },
     "execution_count": 51,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop3 = pop2.merge(areas,how = 'outer')\n",
    "pop3.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 52,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
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       "      <th>2</th>\n",
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       "      <td>Alabama</td>\n",
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       "      <th>4</th>\n",
       "      <td>AL</td>\n",
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      ],
      "text/plain": [
       "  state/region     ages  year  population    state  area (sq. mi)\n",
       "0           AL  under18  2012   1117489.0  Alabama        52423.0\n",
       "1           AL    total  2012   4817528.0  Alabama        52423.0\n",
       "2           AL  under18  2010   1130966.0  Alabama        52423.0\n",
       "3           AL    total  2010   4785570.0  Alabama        52423.0\n",
       "4           AL  under18  2011   1125763.0  Alabama        52423.0"
      ]
     },
     "execution_count": 52,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop3.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 53,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region     False\n",
       "ages             False\n",
       "year             False\n",
       "population       False\n",
       "state            False\n",
       "area (sq. mi)     True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 53,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop3.isnull().any()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 54,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
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       "      <td>311582564.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2522</th>\n",
       "      <td>USA</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>73708179.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2523</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>313873685.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     state/region     ages  year   population         state  area (sq. mi)\n",
       "2476          USA  under18  1990   64218512.0  United State            NaN\n",
       "2477          USA    total  1990  249622814.0  United State            NaN\n",
       "2478          USA    total  1991  252980942.0  United State            NaN\n",
       "2479          USA  under18  1991   65313018.0  United State            NaN\n",
       "2480          USA  under18  1992   66509177.0  United State            NaN\n",
       "2481          USA    total  1992  256514231.0  United State            NaN\n",
       "2482          USA    total  1993  259918595.0  United State            NaN\n",
       "2483          USA  under18  1993   67594938.0  United State            NaN\n",
       "2484          USA  under18  1994   68640936.0  United State            NaN\n",
       "2485          USA    total  1994  263125826.0  United State            NaN\n",
       "2486          USA  under18  1995   69473140.0  United State            NaN\n",
       "2487          USA  under18  1996   70233512.0  United State            NaN\n",
       "2488          USA    total  1995  266278403.0  United State            NaN\n",
       "2489          USA    total  1996  269394291.0  United State            NaN\n",
       "2490          USA    total  1997  272646932.0  United State            NaN\n",
       "2491          USA  under18  1997   70920738.0  United State            NaN\n",
       "2492          USA  under18  1998   71431406.0  United State            NaN\n",
       "2493          USA    total  1998  275854116.0  United State            NaN\n",
       "2494          USA  under18  1999   71946051.0  United State            NaN\n",
       "2495          USA    total  2000  282162411.0  United State            NaN\n",
       "2496          USA  under18  2000   72376189.0  United State            NaN\n",
       "2497          USA    total  1999  279040181.0  United State            NaN\n",
       "2498          USA    total  2001  284968955.0  United State            NaN\n",
       "2499          USA  under18  2001   72671175.0  United State            NaN\n",
       "2500          USA    total  2002  287625193.0  United State            NaN\n",
       "2501          USA  under18  2002   72936457.0  United State            NaN\n",
       "2502          USA    total  2003  290107933.0  United State            NaN\n",
       "2503          USA  under18  2003   73100758.0  United State            NaN\n",
       "2504          USA    total  2004  292805298.0  United State            NaN\n",
       "2505          USA  under18  2004   73297735.0  United State            NaN\n",
       "2506          USA    total  2005  295516599.0  United State            NaN\n",
       "2507          USA  under18  2005   73523669.0  United State            NaN\n",
       "2508          USA    total  2006  298379912.0  United State            NaN\n",
       "2509          USA  under18  2006   73757714.0  United State            NaN\n",
       "2510          USA    total  2007  301231207.0  United State            NaN\n",
       "2511          USA  under18  2007   74019405.0  United State            NaN\n",
       "2512          USA    total  2008  304093966.0  United State            NaN\n",
       "2513          USA  under18  2008   74104602.0  United State            NaN\n",
       "2514          USA  under18  2013   73585872.0  United State            NaN\n",
       "2515          USA    total  2013  316128839.0  United State            NaN\n",
       "2516          USA    total  2009  306771529.0  United State            NaN\n",
       "2517          USA  under18  2009   74134167.0  United State            NaN\n",
       "2518          USA  under18  2010   74119556.0  United State            NaN\n",
       "2519          USA    total  2010  309326295.0  United State            NaN\n",
       "2520          USA  under18  2011   73902222.0  United State            NaN\n",
       "2521          USA    total  2011  311582564.0  United State            NaN\n",
       "2522          USA  under18  2012   73708179.0  United State            NaN\n",
       "2523          USA    total  2012  313873685.0  United State            NaN"
      ]
     },
     "execution_count": 54,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cond = pop3['area (sq. mi)'].isnull()\n",
    "pop3[cond]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 58,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3790399"
      ]
     },
     "execution_count": 58,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "a = areas['area (sq. mi)'].sum()\n",
    "a"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 60,
   "metadata": {},
   "outputs": [
    {
     "name": "stderr",
     "output_type": "stream",
     "text": [
      "d:\\python36\\lib\\site-packages\\ipykernel_launcher.py:3: SettingWithCopyWarning: \n",
      "A value is trying to be set on a copy of a slice from a DataFrame\n",
      "\n",
      "See the caveats in the documentation: http://pandas.pydata.org/pandas-docs/stable/indexing.html#indexing-view-versus-copy\n",
      "  This is separate from the ipykernel package so we can avoid doing imports until\n"
     ]
    }
   ],
   "source": [
    "cond = pop3['state'] == \"United State\"\n",
    "\n",
    "pop3['area (sq. mi)'][cond] = a"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 61,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "state/region     True\n",
       "ages             True\n",
       "year             True\n",
       "population       True\n",
       "state            True\n",
       "area (sq. mi)    True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 61,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop3.notnull().all()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 62,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population    state  area (sq. mi)\n",
       "0           AL  under18  2012   1117489.0  Alabama        52423.0\n",
       "1           AL    total  2012   4817528.0  Alabama        52423.0\n",
       "2           AL  under18  2010   1130966.0  Alabama        52423.0\n",
       "3           AL    total  2010   4785570.0  Alabama        52423.0\n",
       "4           AL  under18  2011   1125763.0  Alabama        52423.0"
      ]
     },
     "execution_count": 62,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop3.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 66,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0       21.3\n",
       "1       91.9\n",
       "2       21.6\n",
       "3       91.3\n",
       "4       21.5\n",
       "5       91.6\n",
       "6       90.8\n",
       "7       21.6\n",
       "8       21.2\n",
       "9       92.2\n",
       "10      89.1\n",
       "11      21.6\n",
       "12      90.0\n",
       "13      21.6\n",
       "14      87.2\n",
       "15      21.3\n",
       "16      88.3\n",
       "17      21.5\n",
       "18      86.4\n",
       "19      21.2\n",
       "20      85.9\n",
       "21      21.2\n",
       "22      85.2\n",
       "23      21.4\n",
       "24      85.5\n",
       "25      21.3\n",
       "26      21.4\n",
       "27      84.5\n",
       "28      84.9\n",
       "29      21.4\n",
       "        ... \n",
       "2494    19.0\n",
       "2495    74.4\n",
       "2496    19.1\n",
       "2497    73.6\n",
       "2498    75.2\n",
       "2499    19.2\n",
       "2500    75.9\n",
       "2501    19.2\n",
       "2502    76.5\n",
       "2503    19.3\n",
       "2504    77.2\n",
       "2505    19.3\n",
       "2506    78.0\n",
       "2507    19.4\n",
       "2508    78.7\n",
       "2509    19.5\n",
       "2510    79.5\n",
       "2511    19.5\n",
       "2512    80.2\n",
       "2513    19.6\n",
       "2514    19.4\n",
       "2515    83.4\n",
       "2516    80.9\n",
       "2517    19.6\n",
       "2518    19.6\n",
       "2519    81.6\n",
       "2520    19.5\n",
       "2521    82.2\n",
       "2522    19.4\n",
       "2523    82.8\n",
       "Length: 2524, dtype: float64"
      ]
     },
     "execution_count": 66,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop_density = (pop3['population']/pop3['area (sq. mi)']).round(1)\n",
    "pop_density"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 67,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>21.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>91.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>21.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>91.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>90.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>21.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>92.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>89.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>11</th>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>12</th>\n",
       "      <td>90.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>14</th>\n",
       "      <td>87.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>15</th>\n",
       "      <td>21.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>16</th>\n",
       "      <td>88.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>17</th>\n",
       "      <td>21.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>18</th>\n",
       "      <td>86.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>19</th>\n",
       "      <td>21.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>20</th>\n",
       "      <td>85.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>21</th>\n",
       "      <td>21.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>22</th>\n",
       "      <td>85.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>23</th>\n",
       "      <td>21.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>24</th>\n",
       "      <td>85.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>21.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>26</th>\n",
       "      <td>21.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>27</th>\n",
       "      <td>84.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>28</th>\n",
       "      <td>84.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>29</th>\n",
       "      <td>21.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>...</th>\n",
       "      <td>...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2494</th>\n",
       "      <td>19.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2495</th>\n",
       "      <td>74.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2496</th>\n",
       "      <td>19.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2497</th>\n",
       "      <td>73.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2498</th>\n",
       "      <td>75.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2499</th>\n",
       "      <td>19.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2500</th>\n",
       "      <td>75.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2501</th>\n",
       "      <td>19.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2502</th>\n",
       "      <td>76.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2503</th>\n",
       "      <td>19.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2504</th>\n",
       "      <td>77.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2505</th>\n",
       "      <td>19.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2506</th>\n",
       "      <td>78.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2507</th>\n",
       "      <td>19.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2508</th>\n",
       "      <td>78.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2509</th>\n",
       "      <td>19.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2510</th>\n",
       "      <td>79.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2511</th>\n",
       "      <td>19.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2512</th>\n",
       "      <td>80.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2513</th>\n",
       "      <td>19.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2514</th>\n",
       "      <td>19.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2515</th>\n",
       "      <td>83.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2516</th>\n",
       "      <td>80.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2517</th>\n",
       "      <td>19.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2518</th>\n",
       "      <td>19.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2519</th>\n",
       "      <td>81.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2520</th>\n",
       "      <td>19.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2521</th>\n",
       "      <td>82.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2522</th>\n",
       "      <td>19.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2523</th>\n",
       "      <td>82.8</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>2524 rows × 1 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "         0\n",
       "0     21.3\n",
       "1     91.9\n",
       "2     21.6\n",
       "3     91.3\n",
       "4     21.5\n",
       "5     91.6\n",
       "6     90.8\n",
       "7     21.6\n",
       "8     21.2\n",
       "9     92.2\n",
       "10    89.1\n",
       "11    21.6\n",
       "12    90.0\n",
       "13    21.6\n",
       "14    87.2\n",
       "15    21.3\n",
       "16    88.3\n",
       "17    21.5\n",
       "18    86.4\n",
       "19    21.2\n",
       "20    85.9\n",
       "21    21.2\n",
       "22    85.2\n",
       "23    21.4\n",
       "24    85.5\n",
       "25    21.3\n",
       "26    21.4\n",
       "27    84.5\n",
       "28    84.9\n",
       "29    21.4\n",
       "...    ...\n",
       "2494  19.0\n",
       "2495  74.4\n",
       "2496  19.1\n",
       "2497  73.6\n",
       "2498  75.2\n",
       "2499  19.2\n",
       "2500  75.9\n",
       "2501  19.2\n",
       "2502  76.5\n",
       "2503  19.3\n",
       "2504  77.2\n",
       "2505  19.3\n",
       "2506  78.0\n",
       "2507  19.4\n",
       "2508  78.7\n",
       "2509  19.5\n",
       "2510  79.5\n",
       "2511  19.5\n",
       "2512  80.2\n",
       "2513  19.6\n",
       "2514  19.4\n",
       "2515  83.4\n",
       "2516  80.9\n",
       "2517  19.6\n",
       "2518  19.6\n",
       "2519  81.6\n",
       "2520  19.5\n",
       "2521  82.2\n",
       "2522  19.4\n",
       "2523  82.8\n",
       "\n",
       "[2524 rows x 1 columns]"
      ]
     },
     "execution_count": 67,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop_density = DataFrame(pop_density)\n",
    "pop_density"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 68,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
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       "    .dataframe tbody tr th:only-of-type {\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>pop_density</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>21.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>91.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>21.5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   pop_density\n",
       "0         21.3\n",
       "1         91.9\n",
       "2         21.6\n",
       "3         91.3\n",
       "4         21.5"
      ]
     },
     "execution_count": 68,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop_density.columns = ['pop_density']\n",
    "pop_density.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "      <th>pop_density</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2012</td>\n",
       "      <td>1117489.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>21.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2010</td>\n",
       "      <td>1130966.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>21.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2010</td>\n",
       "      <td>4785570.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>91.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>AL</td>\n",
       "      <td>under18</td>\n",
       "      <td>2011</td>\n",
       "      <td>1125763.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>21.5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  state/region     ages  year  population    state  area (sq. mi)  pop_density\n",
       "0           AL  under18  2012   1117489.0  Alabama        52423.0         21.3\n",
       "1           AL    total  2012   4817528.0  Alabama        52423.0         91.9\n",
       "2           AL  under18  2010   1130966.0  Alabama        52423.0         21.6\n",
       "3           AL    total  2010   4785570.0  Alabama        52423.0         91.3\n",
       "4           AL  under18  2011   1125763.0  Alabama        52423.0         21.5"
      ]
     },
     "execution_count": 69,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop4 = pop3.merge(pop_density,left_index=True,right_index=True)\n",
    "pop4.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 70,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array([2012, 2010, 2011, 2009, 2013, 2007, 2008, 2005, 2006, 2004, 2003,\n",
       "       2001, 2002, 1999, 2000, 1998, 1997, 1996, 1995, 1994, 1993, 1992,\n",
       "       1991, 1990], dtype=int64)"
      ]
     },
     "execution_count": 70,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop4['year'].unique()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 71,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['under18', 'total'], dtype=object)"
      ]
     },
     "execution_count": 71,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop4['ages'].unique()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 73,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "\n",
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       "\n",
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       "        text-align: right;\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>state/region</th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "      <th>pop_density</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>AL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>95</th>\n",
       "      <td>AK</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>730307.0</td>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425.0</td>\n",
       "      <td>1.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>97</th>\n",
       "      <td>AZ</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6551149.0</td>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006.0</td>\n",
       "      <td>57.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>191</th>\n",
       "      <td>AR</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2949828.0</td>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182.0</td>\n",
       "      <td>55.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>193</th>\n",
       "      <td>CA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>37999878.0</td>\n",
       "      <td>California</td>\n",
       "      <td>163707.0</td>\n",
       "      <td>232.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>287</th>\n",
       "      <td>CO</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5189458.0</td>\n",
       "      <td>Colorado</td>\n",
       "      <td>104100.0</td>\n",
       "      <td>49.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>289</th>\n",
       "      <td>CT</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3591765.0</td>\n",
       "      <td>Connecticut</td>\n",
       "      <td>5544.0</td>\n",
       "      <td>647.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>383</th>\n",
       "      <td>DE</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>917053.0</td>\n",
       "      <td>Delaware</td>\n",
       "      <td>1954.0</td>\n",
       "      <td>469.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>385</th>\n",
       "      <td>DC</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>633427.0</td>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>68.0</td>\n",
       "      <td>9315.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>479</th>\n",
       "      <td>FL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19320749.0</td>\n",
       "      <td>Florida</td>\n",
       "      <td>65758.0</td>\n",
       "      <td>293.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>480</th>\n",
       "      <td>GA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9915646.0</td>\n",
       "      <td>Georgia</td>\n",
       "      <td>59441.0</td>\n",
       "      <td>166.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>575</th>\n",
       "      <td>HI</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1390090.0</td>\n",
       "      <td>Hawaii</td>\n",
       "      <td>10932.0</td>\n",
       "      <td>127.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>576</th>\n",
       "      <td>ID</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1595590.0</td>\n",
       "      <td>Idaho</td>\n",
       "      <td>83574.0</td>\n",
       "      <td>19.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>671</th>\n",
       "      <td>IL</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12868192.0</td>\n",
       "      <td>Illinois</td>\n",
       "      <td>57918.0</td>\n",
       "      <td>222.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>672</th>\n",
       "      <td>IN</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6537782.0</td>\n",
       "      <td>Indiana</td>\n",
       "      <td>36420.0</td>\n",
       "      <td>179.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>767</th>\n",
       "      <td>IA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3075039.0</td>\n",
       "      <td>Iowa</td>\n",
       "      <td>56276.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>768</th>\n",
       "      <td>KS</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2885398.0</td>\n",
       "      <td>Kansas</td>\n",
       "      <td>82282.0</td>\n",
       "      <td>35.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>863</th>\n",
       "      <td>KY</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4379730.0</td>\n",
       "      <td>Kentucky</td>\n",
       "      <td>40411.0</td>\n",
       "      <td>108.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>864</th>\n",
       "      <td>LA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4602134.0</td>\n",
       "      <td>Louisiana</td>\n",
       "      <td>51843.0</td>\n",
       "      <td>88.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>959</th>\n",
       "      <td>ME</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1328501.0</td>\n",
       "      <td>Maine</td>\n",
       "      <td>35387.0</td>\n",
       "      <td>37.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>960</th>\n",
       "      <td>MD</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5884868.0</td>\n",
       "      <td>Maryland</td>\n",
       "      <td>12407.0</td>\n",
       "      <td>474.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1055</th>\n",
       "      <td>MA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6645303.0</td>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>10555.0</td>\n",
       "      <td>629.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1056</th>\n",
       "      <td>MI</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9882519.0</td>\n",
       "      <td>Michigan</td>\n",
       "      <td>96810.0</td>\n",
       "      <td>102.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1151</th>\n",
       "      <td>MN</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5379646.0</td>\n",
       "      <td>Minnesota</td>\n",
       "      <td>86943.0</td>\n",
       "      <td>61.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1152</th>\n",
       "      <td>MS</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2986450.0</td>\n",
       "      <td>Mississippi</td>\n",
       "      <td>48434.0</td>\n",
       "      <td>61.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1247</th>\n",
       "      <td>MO</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6024522.0</td>\n",
       "      <td>Missouri</td>\n",
       "      <td>69709.0</td>\n",
       "      <td>86.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1248</th>\n",
       "      <td>MT</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1005494.0</td>\n",
       "      <td>Montana</td>\n",
       "      <td>147046.0</td>\n",
       "      <td>6.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1343</th>\n",
       "      <td>NE</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1855350.0</td>\n",
       "      <td>Nebraska</td>\n",
       "      <td>77358.0</td>\n",
       "      <td>24.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1344</th>\n",
       "      <td>NV</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2754354.0</td>\n",
       "      <td>Nevada</td>\n",
       "      <td>110567.0</td>\n",
       "      <td>24.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1439</th>\n",
       "      <td>NH</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1321617.0</td>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>9351.0</td>\n",
       "      <td>141.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1440</th>\n",
       "      <td>NJ</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8867749.0</td>\n",
       "      <td>New Jersey</td>\n",
       "      <td>8722.0</td>\n",
       "      <td>1016.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1535</th>\n",
       "      <td>NM</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2083540.0</td>\n",
       "      <td>New Mexico</td>\n",
       "      <td>121593.0</td>\n",
       "      <td>17.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1536</th>\n",
       "      <td>NY</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19576125.0</td>\n",
       "      <td>New York</td>\n",
       "      <td>54475.0</td>\n",
       "      <td>359.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1631</th>\n",
       "      <td>NC</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9748364.0</td>\n",
       "      <td>North Carolina</td>\n",
       "      <td>53821.0</td>\n",
       "      <td>181.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1632</th>\n",
       "      <td>ND</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>701345.0</td>\n",
       "      <td>North Dakota</td>\n",
       "      <td>70704.0</td>\n",
       "      <td>9.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1727</th>\n",
       "      <td>OH</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>11553031.0</td>\n",
       "      <td>Ohio</td>\n",
       "      <td>44828.0</td>\n",
       "      <td>257.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1728</th>\n",
       "      <td>OK</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3815780.0</td>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>69903.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1823</th>\n",
       "      <td>OR</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3899801.0</td>\n",
       "      <td>Oregon</td>\n",
       "      <td>98386.0</td>\n",
       "      <td>39.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1824</th>\n",
       "      <td>PA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12764475.0</td>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>46058.0</td>\n",
       "      <td>277.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1919</th>\n",
       "      <td>RI</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1050304.0</td>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>1545.0</td>\n",
       "      <td>679.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1920</th>\n",
       "      <td>SC</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4723417.0</td>\n",
       "      <td>South Carolina</td>\n",
       "      <td>32007.0</td>\n",
       "      <td>147.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2015</th>\n",
       "      <td>SD</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>834047.0</td>\n",
       "      <td>South Dakota</td>\n",
       "      <td>77121.0</td>\n",
       "      <td>10.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2016</th>\n",
       "      <td>TN</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6454914.0</td>\n",
       "      <td>Tennessee</td>\n",
       "      <td>42146.0</td>\n",
       "      <td>153.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2111</th>\n",
       "      <td>TX</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>26060796.0</td>\n",
       "      <td>Texas</td>\n",
       "      <td>268601.0</td>\n",
       "      <td>97.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2112</th>\n",
       "      <td>UT</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2854871.0</td>\n",
       "      <td>Utah</td>\n",
       "      <td>84904.0</td>\n",
       "      <td>33.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2207</th>\n",
       "      <td>VT</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>625953.0</td>\n",
       "      <td>Vermont</td>\n",
       "      <td>9615.0</td>\n",
       "      <td>65.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2208</th>\n",
       "      <td>VA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8186628.0</td>\n",
       "      <td>Virginia</td>\n",
       "      <td>42769.0</td>\n",
       "      <td>191.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2303</th>\n",
       "      <td>WA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6895318.0</td>\n",
       "      <td>Washington</td>\n",
       "      <td>71303.0</td>\n",
       "      <td>96.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2304</th>\n",
       "      <td>WV</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1856680.0</td>\n",
       "      <td>West Virginia</td>\n",
       "      <td>24231.0</td>\n",
       "      <td>76.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2399</th>\n",
       "      <td>WI</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5724554.0</td>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>65503.0</td>\n",
       "      <td>87.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2400</th>\n",
       "      <td>WY</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>576626.0</td>\n",
       "      <td>Wyoming</td>\n",
       "      <td>97818.0</td>\n",
       "      <td>5.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2475</th>\n",
       "      <td>PR</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3651545.0</td>\n",
       "      <td>Puerto Rico</td>\n",
       "      <td>3515.0</td>\n",
       "      <td>1038.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2523</th>\n",
       "      <td>USA</td>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>313873685.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>3790399.0</td>\n",
       "      <td>82.8</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     state/region   ages  year   population                 state  area (sq. mi)  pop_density\n",
       "1              AL  total  2012    4817528.0               Alabama        52423.0         91.9\n",
       "95             AK  total  2012     730307.0                Alaska       656425.0          1.1\n",
       "97             AZ  total  2012    6551149.0               Arizona       114006.0         57.5\n",
       "191            AR  total  2012    2949828.0              Arkansas        53182.0         55.5\n",
       "193            CA  total  2012   37999878.0            California       163707.0        232.1\n",
       "287            CO  total  2012    5189458.0              Colorado       104100.0         49.9\n",
       "289            CT  total  2012    3591765.0           Connecticut         5544.0        647.9\n",
       "383            DE  total  2012     917053.0              Delaware         1954.0        469.3\n",
       "385            DC  total  2012     633427.0  District of Columbia           68.0       9315.1\n",
       "479            FL  total  2012   19320749.0               Florida        65758.0        293.8\n",
       "480            GA  total  2012    9915646.0               Georgia        59441.0        166.8\n",
       "575            HI  total  2012    1390090.0                Hawaii        10932.0        127.2\n",
       "576            ID  total  2012    1595590.0                 Idaho        83574.0         19.1\n",
       "671            IL  total  2012   12868192.0              Illinois        57918.0        222.2\n",
       "672            IN  total  2012    6537782.0               Indiana        36420.0        179.5\n",
       "767            IA  total  2012    3075039.0                  Iowa        56276.0         54.6\n",
       "768            KS  total  2012    2885398.0                Kansas        82282.0         35.1\n",
       "863            KY  total  2012    4379730.0              Kentucky        40411.0        108.4\n",
       "864            LA  total  2012    4602134.0             Louisiana        51843.0         88.8\n",
       "959            ME  total  2012    1328501.0                 Maine        35387.0         37.5\n",
       "960            MD  total  2012    5884868.0              Maryland        12407.0        474.3\n",
       "1055           MA  total  2012    6645303.0         Massachusetts        10555.0        629.6\n",
       "1056           MI  total  2012    9882519.0              Michigan        96810.0        102.1\n",
       "1151           MN  total  2012    5379646.0             Minnesota        86943.0         61.9\n",
       "1152           MS  total  2012    2986450.0           Mississippi        48434.0         61.7\n",
       "1247           MO  total  2012    6024522.0              Missouri        69709.0         86.4\n",
       "1248           MT  total  2012    1005494.0               Montana       147046.0          6.8\n",
       "1343           NE  total  2012    1855350.0              Nebraska        77358.0         24.0\n",
       "1344           NV  total  2012    2754354.0                Nevada       110567.0         24.9\n",
       "1439           NH  total  2012    1321617.0         New Hampshire         9351.0        141.3\n",
       "1440           NJ  total  2012    8867749.0            New Jersey         8722.0       1016.7\n",
       "1535           NM  total  2012    2083540.0            New Mexico       121593.0         17.1\n",
       "1536           NY  total  2012   19576125.0              New York        54475.0        359.4\n",
       "1631           NC  total  2012    9748364.0        North Carolina        53821.0        181.1\n",
       "1632           ND  total  2012     701345.0          North Dakota        70704.0          9.9\n",
       "1727           OH  total  2012   11553031.0                  Ohio        44828.0        257.7\n",
       "1728           OK  total  2012    3815780.0              Oklahoma        69903.0         54.6\n",
       "1823           OR  total  2012    3899801.0                Oregon        98386.0         39.6\n",
       "1824           PA  total  2012   12764475.0          Pennsylvania        46058.0        277.1\n",
       "1919           RI  total  2012    1050304.0          Rhode Island         1545.0        679.8\n",
       "1920           SC  total  2012    4723417.0        South Carolina        32007.0        147.6\n",
       "2015           SD  total  2012     834047.0          South Dakota        77121.0         10.8\n",
       "2016           TN  total  2012    6454914.0             Tennessee        42146.0        153.2\n",
       "2111           TX  total  2012   26060796.0                 Texas       268601.0         97.0\n",
       "2112           UT  total  2012    2854871.0                  Utah        84904.0         33.6\n",
       "2207           VT  total  2012     625953.0               Vermont         9615.0         65.1\n",
       "2208           VA  total  2012    8186628.0              Virginia        42769.0        191.4\n",
       "2303           WA  total  2012    6895318.0            Washington        71303.0         96.7\n",
       "2304           WV  total  2012    1856680.0         West Virginia        24231.0         76.6\n",
       "2399           WI  total  2012    5724554.0             Wisconsin        65503.0         87.4\n",
       "2400           WY  total  2012     576626.0               Wyoming        97818.0          5.9\n",
       "2475           PR  total  2012    3651545.0           Puerto Rico         3515.0       1038.8\n",
       "2523          USA  total  2012  313873685.0          United State      3790399.0         82.8"
      ]
     },
     "execution_count": 73,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# 查找2012年美国各州的全民人口数据\n",
    "\n",
    "# pandas非常强大的，可以像查询数据库一样进行数据查询\n",
    "\n",
    "pop5 = pop4.query(\"year == 2012 and ages == 'total'\")\n",
    "pop5"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 78,
   "metadata": {},
   "outputs": [],
   "source": [
    "pop5.set_index(keys = 'state/region',inplace=True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 80,
   "metadata": {
    "collapsed": true
   },
   "outputs": [
    {
     "data": {
      "text/html": [
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "      <th>pop_density</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>state/region</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>AK</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>730307.0</td>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425.0</td>\n",
       "      <td>1.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>576626.0</td>\n",
       "      <td>Wyoming</td>\n",
       "      <td>97818.0</td>\n",
       "      <td>5.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1005494.0</td>\n",
       "      <td>Montana</td>\n",
       "      <td>147046.0</td>\n",
       "      <td>6.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ND</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>701345.0</td>\n",
       "      <td>North Dakota</td>\n",
       "      <td>70704.0</td>\n",
       "      <td>9.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>SD</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>834047.0</td>\n",
       "      <td>South Dakota</td>\n",
       "      <td>77121.0</td>\n",
       "      <td>10.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NM</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2083540.0</td>\n",
       "      <td>New Mexico</td>\n",
       "      <td>121593.0</td>\n",
       "      <td>17.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ID</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1595590.0</td>\n",
       "      <td>Idaho</td>\n",
       "      <td>83574.0</td>\n",
       "      <td>19.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NE</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1855350.0</td>\n",
       "      <td>Nebraska</td>\n",
       "      <td>77358.0</td>\n",
       "      <td>24.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NV</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2754354.0</td>\n",
       "      <td>Nevada</td>\n",
       "      <td>110567.0</td>\n",
       "      <td>24.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>UT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2854871.0</td>\n",
       "      <td>Utah</td>\n",
       "      <td>84904.0</td>\n",
       "      <td>33.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>KS</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2885398.0</td>\n",
       "      <td>Kansas</td>\n",
       "      <td>82282.0</td>\n",
       "      <td>35.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ME</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1328501.0</td>\n",
       "      <td>Maine</td>\n",
       "      <td>35387.0</td>\n",
       "      <td>37.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3899801.0</td>\n",
       "      <td>Oregon</td>\n",
       "      <td>98386.0</td>\n",
       "      <td>39.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CO</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5189458.0</td>\n",
       "      <td>Colorado</td>\n",
       "      <td>104100.0</td>\n",
       "      <td>49.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3075039.0</td>\n",
       "      <td>Iowa</td>\n",
       "      <td>56276.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OK</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3815780.0</td>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>69903.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2949828.0</td>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182.0</td>\n",
       "      <td>55.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AZ</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6551149.0</td>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006.0</td>\n",
       "      <td>57.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MS</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2986450.0</td>\n",
       "      <td>Mississippi</td>\n",
       "      <td>48434.0</td>\n",
       "      <td>61.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5379646.0</td>\n",
       "      <td>Minnesota</td>\n",
       "      <td>86943.0</td>\n",
       "      <td>61.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>VT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>625953.0</td>\n",
       "      <td>Vermont</td>\n",
       "      <td>9615.0</td>\n",
       "      <td>65.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WV</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1856680.0</td>\n",
       "      <td>West Virginia</td>\n",
       "      <td>24231.0</td>\n",
       "      <td>76.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>USA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>313873685.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>3790399.0</td>\n",
       "      <td>82.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MO</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6024522.0</td>\n",
       "      <td>Missouri</td>\n",
       "      <td>69709.0</td>\n",
       "      <td>86.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5724554.0</td>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>65503.0</td>\n",
       "      <td>87.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>LA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4602134.0</td>\n",
       "      <td>Louisiana</td>\n",
       "      <td>51843.0</td>\n",
       "      <td>88.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6895318.0</td>\n",
       "      <td>Washington</td>\n",
       "      <td>71303.0</td>\n",
       "      <td>96.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>TX</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>26060796.0</td>\n",
       "      <td>Texas</td>\n",
       "      <td>268601.0</td>\n",
       "      <td>97.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9882519.0</td>\n",
       "      <td>Michigan</td>\n",
       "      <td>96810.0</td>\n",
       "      <td>102.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>KY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4379730.0</td>\n",
       "      <td>Kentucky</td>\n",
       "      <td>40411.0</td>\n",
       "      <td>108.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>HI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1390090.0</td>\n",
       "      <td>Hawaii</td>\n",
       "      <td>10932.0</td>\n",
       "      <td>127.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NH</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1321617.0</td>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>9351.0</td>\n",
       "      <td>141.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>SC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4723417.0</td>\n",
       "      <td>South Carolina</td>\n",
       "      <td>32007.0</td>\n",
       "      <td>147.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>TN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6454914.0</td>\n",
       "      <td>Tennessee</td>\n",
       "      <td>42146.0</td>\n",
       "      <td>153.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>GA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9915646.0</td>\n",
       "      <td>Georgia</td>\n",
       "      <td>59441.0</td>\n",
       "      <td>166.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6537782.0</td>\n",
       "      <td>Indiana</td>\n",
       "      <td>36420.0</td>\n",
       "      <td>179.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9748364.0</td>\n",
       "      <td>North Carolina</td>\n",
       "      <td>53821.0</td>\n",
       "      <td>181.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>VA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8186628.0</td>\n",
       "      <td>Virginia</td>\n",
       "      <td>42769.0</td>\n",
       "      <td>191.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12868192.0</td>\n",
       "      <td>Illinois</td>\n",
       "      <td>57918.0</td>\n",
       "      <td>222.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>37999878.0</td>\n",
       "      <td>California</td>\n",
       "      <td>163707.0</td>\n",
       "      <td>232.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OH</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>11553031.0</td>\n",
       "      <td>Ohio</td>\n",
       "      <td>44828.0</td>\n",
       "      <td>257.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>PA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12764475.0</td>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>46058.0</td>\n",
       "      <td>277.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>FL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19320749.0</td>\n",
       "      <td>Florida</td>\n",
       "      <td>65758.0</td>\n",
       "      <td>293.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19576125.0</td>\n",
       "      <td>New York</td>\n",
       "      <td>54475.0</td>\n",
       "      <td>359.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>DE</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>917053.0</td>\n",
       "      <td>Delaware</td>\n",
       "      <td>1954.0</td>\n",
       "      <td>469.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MD</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5884868.0</td>\n",
       "      <td>Maryland</td>\n",
       "      <td>12407.0</td>\n",
       "      <td>474.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6645303.0</td>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>10555.0</td>\n",
       "      <td>629.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3591765.0</td>\n",
       "      <td>Connecticut</td>\n",
       "      <td>5544.0</td>\n",
       "      <td>647.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>RI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1050304.0</td>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>1545.0</td>\n",
       "      <td>679.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NJ</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8867749.0</td>\n",
       "      <td>New Jersey</td>\n",
       "      <td>8722.0</td>\n",
       "      <td>1016.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>PR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3651545.0</td>\n",
       "      <td>Puerto Rico</td>\n",
       "      <td>3515.0</td>\n",
       "      <td>1038.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>DC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>633427.0</td>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>68.0</td>\n",
       "      <td>9315.1</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "               ages  year   population                 state  area (sq. mi)  pop_density\n",
       "state/region                                                                            \n",
       "AK            total  2012     730307.0                Alaska       656425.0          1.1\n",
       "WY            total  2012     576626.0               Wyoming        97818.0          5.9\n",
       "MT            total  2012    1005494.0               Montana       147046.0          6.8\n",
       "ND            total  2012     701345.0          North Dakota        70704.0          9.9\n",
       "SD            total  2012     834047.0          South Dakota        77121.0         10.8\n",
       "NM            total  2012    2083540.0            New Mexico       121593.0         17.1\n",
       "ID            total  2012    1595590.0                 Idaho        83574.0         19.1\n",
       "NE            total  2012    1855350.0              Nebraska        77358.0         24.0\n",
       "NV            total  2012    2754354.0                Nevada       110567.0         24.9\n",
       "UT            total  2012    2854871.0                  Utah        84904.0         33.6\n",
       "KS            total  2012    2885398.0                Kansas        82282.0         35.1\n",
       "ME            total  2012    1328501.0                 Maine        35387.0         37.5\n",
       "OR            total  2012    3899801.0                Oregon        98386.0         39.6\n",
       "CO            total  2012    5189458.0              Colorado       104100.0         49.9\n",
       "IA            total  2012    3075039.0                  Iowa        56276.0         54.6\n",
       "OK            total  2012    3815780.0              Oklahoma        69903.0         54.6\n",
       "AR            total  2012    2949828.0              Arkansas        53182.0         55.5\n",
       "AZ            total  2012    6551149.0               Arizona       114006.0         57.5\n",
       "MS            total  2012    2986450.0           Mississippi        48434.0         61.7\n",
       "MN            total  2012    5379646.0             Minnesota        86943.0         61.9\n",
       "VT            total  2012     625953.0               Vermont         9615.0         65.1\n",
       "WV            total  2012    1856680.0         West Virginia        24231.0         76.6\n",
       "USA           total  2012  313873685.0          United State      3790399.0         82.8\n",
       "MO            total  2012    6024522.0              Missouri        69709.0         86.4\n",
       "WI            total  2012    5724554.0             Wisconsin        65503.0         87.4\n",
       "LA            total  2012    4602134.0             Louisiana        51843.0         88.8\n",
       "AL            total  2012    4817528.0               Alabama        52423.0         91.9\n",
       "WA            total  2012    6895318.0            Washington        71303.0         96.7\n",
       "TX            total  2012   26060796.0                 Texas       268601.0         97.0\n",
       "MI            total  2012    9882519.0              Michigan        96810.0        102.1\n",
       "KY            total  2012    4379730.0              Kentucky        40411.0        108.4\n",
       "HI            total  2012    1390090.0                Hawaii        10932.0        127.2\n",
       "NH            total  2012    1321617.0         New Hampshire         9351.0        141.3\n",
       "SC            total  2012    4723417.0        South Carolina        32007.0        147.6\n",
       "TN            total  2012    6454914.0             Tennessee        42146.0        153.2\n",
       "GA            total  2012    9915646.0               Georgia        59441.0        166.8\n",
       "IN            total  2012    6537782.0               Indiana        36420.0        179.5\n",
       "NC            total  2012    9748364.0        North Carolina        53821.0        181.1\n",
       "VA            total  2012    8186628.0              Virginia        42769.0        191.4\n",
       "IL            total  2012   12868192.0              Illinois        57918.0        222.2\n",
       "CA            total  2012   37999878.0            California       163707.0        232.1\n",
       "OH            total  2012   11553031.0                  Ohio        44828.0        257.7\n",
       "PA            total  2012   12764475.0          Pennsylvania        46058.0        277.1\n",
       "FL            total  2012   19320749.0               Florida        65758.0        293.8\n",
       "NY            total  2012   19576125.0              New York        54475.0        359.4\n",
       "DE            total  2012     917053.0              Delaware         1954.0        469.3\n",
       "MD            total  2012    5884868.0              Maryland        12407.0        474.3\n",
       "MA            total  2012    6645303.0         Massachusetts        10555.0        629.6\n",
       "CT            total  2012    3591765.0           Connecticut         5544.0        647.9\n",
       "RI            total  2012    1050304.0          Rhode Island         1545.0        679.8\n",
       "NJ            total  2012    8867749.0            New Jersey         8722.0       1016.7\n",
       "PR            total  2012    3651545.0           Puerto Rico         3515.0       1038.8\n",
       "DC            total  2012     633427.0  District of Columbia           68.0       9315.1"
      ]
     },
     "execution_count": 80,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop5.sort_values(by = 'pop_density')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 81,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
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       "\n",
       "    .dataframe thead th {\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>ages</th>\n",
       "      <th>year</th>\n",
       "      <th>population</th>\n",
       "      <th>state</th>\n",
       "      <th>area (sq. mi)</th>\n",
       "      <th>pop_density</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>state/region</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>DC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>633427.0</td>\n",
       "      <td>District of Columbia</td>\n",
       "      <td>68.0</td>\n",
       "      <td>9315.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>PR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3651545.0</td>\n",
       "      <td>Puerto Rico</td>\n",
       "      <td>3515.0</td>\n",
       "      <td>1038.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NJ</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8867749.0</td>\n",
       "      <td>New Jersey</td>\n",
       "      <td>8722.0</td>\n",
       "      <td>1016.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>RI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1050304.0</td>\n",
       "      <td>Rhode Island</td>\n",
       "      <td>1545.0</td>\n",
       "      <td>679.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3591765.0</td>\n",
       "      <td>Connecticut</td>\n",
       "      <td>5544.0</td>\n",
       "      <td>647.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6645303.0</td>\n",
       "      <td>Massachusetts</td>\n",
       "      <td>10555.0</td>\n",
       "      <td>629.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MD</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5884868.0</td>\n",
       "      <td>Maryland</td>\n",
       "      <td>12407.0</td>\n",
       "      <td>474.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>DE</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>917053.0</td>\n",
       "      <td>Delaware</td>\n",
       "      <td>1954.0</td>\n",
       "      <td>469.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19576125.0</td>\n",
       "      <td>New York</td>\n",
       "      <td>54475.0</td>\n",
       "      <td>359.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>FL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>19320749.0</td>\n",
       "      <td>Florida</td>\n",
       "      <td>65758.0</td>\n",
       "      <td>293.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>PA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12764475.0</td>\n",
       "      <td>Pennsylvania</td>\n",
       "      <td>46058.0</td>\n",
       "      <td>277.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OH</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>11553031.0</td>\n",
       "      <td>Ohio</td>\n",
       "      <td>44828.0</td>\n",
       "      <td>257.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>37999878.0</td>\n",
       "      <td>California</td>\n",
       "      <td>163707.0</td>\n",
       "      <td>232.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>12868192.0</td>\n",
       "      <td>Illinois</td>\n",
       "      <td>57918.0</td>\n",
       "      <td>222.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>VA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>8186628.0</td>\n",
       "      <td>Virginia</td>\n",
       "      <td>42769.0</td>\n",
       "      <td>191.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9748364.0</td>\n",
       "      <td>North Carolina</td>\n",
       "      <td>53821.0</td>\n",
       "      <td>181.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6537782.0</td>\n",
       "      <td>Indiana</td>\n",
       "      <td>36420.0</td>\n",
       "      <td>179.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>GA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9915646.0</td>\n",
       "      <td>Georgia</td>\n",
       "      <td>59441.0</td>\n",
       "      <td>166.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>TN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6454914.0</td>\n",
       "      <td>Tennessee</td>\n",
       "      <td>42146.0</td>\n",
       "      <td>153.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>SC</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4723417.0</td>\n",
       "      <td>South Carolina</td>\n",
       "      <td>32007.0</td>\n",
       "      <td>147.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NH</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1321617.0</td>\n",
       "      <td>New Hampshire</td>\n",
       "      <td>9351.0</td>\n",
       "      <td>141.3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>HI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1390090.0</td>\n",
       "      <td>Hawaii</td>\n",
       "      <td>10932.0</td>\n",
       "      <td>127.2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>KY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4379730.0</td>\n",
       "      <td>Kentucky</td>\n",
       "      <td>40411.0</td>\n",
       "      <td>108.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>9882519.0</td>\n",
       "      <td>Michigan</td>\n",
       "      <td>96810.0</td>\n",
       "      <td>102.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>TX</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>26060796.0</td>\n",
       "      <td>Texas</td>\n",
       "      <td>268601.0</td>\n",
       "      <td>97.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6895318.0</td>\n",
       "      <td>Washington</td>\n",
       "      <td>71303.0</td>\n",
       "      <td>96.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AL</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4817528.0</td>\n",
       "      <td>Alabama</td>\n",
       "      <td>52423.0</td>\n",
       "      <td>91.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>LA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>4602134.0</td>\n",
       "      <td>Louisiana</td>\n",
       "      <td>51843.0</td>\n",
       "      <td>88.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WI</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5724554.0</td>\n",
       "      <td>Wisconsin</td>\n",
       "      <td>65503.0</td>\n",
       "      <td>87.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MO</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6024522.0</td>\n",
       "      <td>Missouri</td>\n",
       "      <td>69709.0</td>\n",
       "      <td>86.4</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>USA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>313873685.0</td>\n",
       "      <td>United State</td>\n",
       "      <td>3790399.0</td>\n",
       "      <td>82.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WV</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1856680.0</td>\n",
       "      <td>West Virginia</td>\n",
       "      <td>24231.0</td>\n",
       "      <td>76.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>VT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>625953.0</td>\n",
       "      <td>Vermont</td>\n",
       "      <td>9615.0</td>\n",
       "      <td>65.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MN</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5379646.0</td>\n",
       "      <td>Minnesota</td>\n",
       "      <td>86943.0</td>\n",
       "      <td>61.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MS</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2986450.0</td>\n",
       "      <td>Mississippi</td>\n",
       "      <td>48434.0</td>\n",
       "      <td>61.7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AZ</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>6551149.0</td>\n",
       "      <td>Arizona</td>\n",
       "      <td>114006.0</td>\n",
       "      <td>57.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2949828.0</td>\n",
       "      <td>Arkansas</td>\n",
       "      <td>53182.0</td>\n",
       "      <td>55.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OK</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3815780.0</td>\n",
       "      <td>Oklahoma</td>\n",
       "      <td>69903.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>IA</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3075039.0</td>\n",
       "      <td>Iowa</td>\n",
       "      <td>56276.0</td>\n",
       "      <td>54.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>CO</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>5189458.0</td>\n",
       "      <td>Colorado</td>\n",
       "      <td>104100.0</td>\n",
       "      <td>49.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>OR</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>3899801.0</td>\n",
       "      <td>Oregon</td>\n",
       "      <td>98386.0</td>\n",
       "      <td>39.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ME</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1328501.0</td>\n",
       "      <td>Maine</td>\n",
       "      <td>35387.0</td>\n",
       "      <td>37.5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>KS</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2885398.0</td>\n",
       "      <td>Kansas</td>\n",
       "      <td>82282.0</td>\n",
       "      <td>35.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>UT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2854871.0</td>\n",
       "      <td>Utah</td>\n",
       "      <td>84904.0</td>\n",
       "      <td>33.6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NV</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2754354.0</td>\n",
       "      <td>Nevada</td>\n",
       "      <td>110567.0</td>\n",
       "      <td>24.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NE</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1855350.0</td>\n",
       "      <td>Nebraska</td>\n",
       "      <td>77358.0</td>\n",
       "      <td>24.0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ID</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1595590.0</td>\n",
       "      <td>Idaho</td>\n",
       "      <td>83574.0</td>\n",
       "      <td>19.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>NM</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>2083540.0</td>\n",
       "      <td>New Mexico</td>\n",
       "      <td>121593.0</td>\n",
       "      <td>17.1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>SD</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>834047.0</td>\n",
       "      <td>South Dakota</td>\n",
       "      <td>77121.0</td>\n",
       "      <td>10.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>ND</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>701345.0</td>\n",
       "      <td>North Dakota</td>\n",
       "      <td>70704.0</td>\n",
       "      <td>9.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>MT</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>1005494.0</td>\n",
       "      <td>Montana</td>\n",
       "      <td>147046.0</td>\n",
       "      <td>6.8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>WY</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>576626.0</td>\n",
       "      <td>Wyoming</td>\n",
       "      <td>97818.0</td>\n",
       "      <td>5.9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>AK</th>\n",
       "      <td>total</td>\n",
       "      <td>2012</td>\n",
       "      <td>730307.0</td>\n",
       "      <td>Alaska</td>\n",
       "      <td>656425.0</td>\n",
       "      <td>1.1</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "               ages  year   population                 state  area (sq. mi)  pop_density\n",
       "state/region                                                                            \n",
       "DC            total  2012     633427.0  District of Columbia           68.0       9315.1\n",
       "PR            total  2012    3651545.0           Puerto Rico         3515.0       1038.8\n",
       "NJ            total  2012    8867749.0            New Jersey         8722.0       1016.7\n",
       "RI            total  2012    1050304.0          Rhode Island         1545.0        679.8\n",
       "CT            total  2012    3591765.0           Connecticut         5544.0        647.9\n",
       "MA            total  2012    6645303.0         Massachusetts        10555.0        629.6\n",
       "MD            total  2012    5884868.0              Maryland        12407.0        474.3\n",
       "DE            total  2012     917053.0              Delaware         1954.0        469.3\n",
       "NY            total  2012   19576125.0              New York        54475.0        359.4\n",
       "FL            total  2012   19320749.0               Florida        65758.0        293.8\n",
       "PA            total  2012   12764475.0          Pennsylvania        46058.0        277.1\n",
       "OH            total  2012   11553031.0                  Ohio        44828.0        257.7\n",
       "CA            total  2012   37999878.0            California       163707.0        232.1\n",
       "IL            total  2012   12868192.0              Illinois        57918.0        222.2\n",
       "VA            total  2012    8186628.0              Virginia        42769.0        191.4\n",
       "NC            total  2012    9748364.0        North Carolina        53821.0        181.1\n",
       "IN            total  2012    6537782.0               Indiana        36420.0        179.5\n",
       "GA            total  2012    9915646.0               Georgia        59441.0        166.8\n",
       "TN            total  2012    6454914.0             Tennessee        42146.0        153.2\n",
       "SC            total  2012    4723417.0        South Carolina        32007.0        147.6\n",
       "NH            total  2012    1321617.0         New Hampshire         9351.0        141.3\n",
       "HI            total  2012    1390090.0                Hawaii        10932.0        127.2\n",
       "KY            total  2012    4379730.0              Kentucky        40411.0        108.4\n",
       "MI            total  2012    9882519.0              Michigan        96810.0        102.1\n",
       "TX            total  2012   26060796.0                 Texas       268601.0         97.0\n",
       "WA            total  2012    6895318.0            Washington        71303.0         96.7\n",
       "AL            total  2012    4817528.0               Alabama        52423.0         91.9\n",
       "LA            total  2012    4602134.0             Louisiana        51843.0         88.8\n",
       "WI            total  2012    5724554.0             Wisconsin        65503.0         87.4\n",
       "MO            total  2012    6024522.0              Missouri        69709.0         86.4\n",
       "USA           total  2012  313873685.0          United State      3790399.0         82.8\n",
       "WV            total  2012    1856680.0         West Virginia        24231.0         76.6\n",
       "VT            total  2012     625953.0               Vermont         9615.0         65.1\n",
       "MN            total  2012    5379646.0             Minnesota        86943.0         61.9\n",
       "MS            total  2012    2986450.0           Mississippi        48434.0         61.7\n",
       "AZ            total  2012    6551149.0               Arizona       114006.0         57.5\n",
       "AR            total  2012    2949828.0              Arkansas        53182.0         55.5\n",
       "OK            total  2012    3815780.0              Oklahoma        69903.0         54.6\n",
       "IA            total  2012    3075039.0                  Iowa        56276.0         54.6\n",
       "CO            total  2012    5189458.0              Colorado       104100.0         49.9\n",
       "OR            total  2012    3899801.0                Oregon        98386.0         39.6\n",
       "ME            total  2012    1328501.0                 Maine        35387.0         37.5\n",
       "KS            total  2012    2885398.0                Kansas        82282.0         35.1\n",
       "UT            total  2012    2854871.0                  Utah        84904.0         33.6\n",
       "NV            total  2012    2754354.0                Nevada       110567.0         24.9\n",
       "NE            total  2012    1855350.0              Nebraska        77358.0         24.0\n",
       "ID            total  2012    1595590.0                 Idaho        83574.0         19.1\n",
       "NM            total  2012    2083540.0            New Mexico       121593.0         17.1\n",
       "SD            total  2012     834047.0          South Dakota        77121.0         10.8\n",
       "ND            total  2012     701345.0          North Dakota        70704.0          9.9\n",
       "MT            total  2012    1005494.0               Montana       147046.0          6.8\n",
       "WY            total  2012     576626.0               Wyoming        97818.0          5.9\n",
       "AK            total  2012     730307.0                Alaska       656425.0          1.1"
      ]
     },
     "execution_count": 81,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "pop5.sort_values(by='pop_density',ascending=False)"
   ]
  }
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